/* CSS Variables for Theme Support */
:root {
    /* Light Mode Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-sidebar: #2d3748;
    --bg-content: #ffffff;
    --text-primary: #1a202c;
    --text-secondary: #2d3748;
    --text-muted: #4a5568;
    --border-primary: #e2e8f0;
    --border-secondary: #4a5568;
    --accent-primary: #3182ce;
    --accent-secondary: #2c5282;
    --scrollbar-track: #f7fafc;
    --scrollbar-thumb: #cbd5e0;
    --scrollbar-thumb-hover: #a0aec0;
    --code-bg: #ffffff;
    --code-border: #e5e7eb;
    --code-text: #f97316;
    --blockquote-bg: #f7fafc;
    --blockquote-border: #e2e8f0;
    --table-stripe: #f7fafc;
    --shadow-light: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.05);
    --header-height: 60px;
}

/* Dark Mode Colors */
[data-theme="dark"] {
    --bg-primary: #1a202c;
    --bg-secondary: #2d3748;
    --bg-sidebar: #1a202c;
    --bg-content: #1a202c;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-muted: #a0aec0;
    --border-primary: #4a5568;
    --border-secondary: #2d3748;
    --accent-primary: #63b3ed;
    --accent-secondary: #90cdf4;
    --scrollbar-track: #2d3748;
    --scrollbar-thumb: #4a5568;
    --scrollbar-thumb-hover: #718096;
    --code-bg: #2d3748;
    --code-border: #4a5568;
    --code-text: #fbbf24;
    --blockquote-bg: #2d3748;
    --blockquote-border: #4a5568;
    --table-stripe: #2d3748;
    --shadow-light: rgba(0, 0, 0, 0.3);
    --shadow-medium: rgba(0, 0, 0, 0.2);
}

/* Modern CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

*:focus {
    outline: none;
    border: none;
}

*:focus-visible {
    outline: none;
    border: none;
}

html, body {
    height: 100%;
}

body {
    font-family: 'IBM Plex Sans KR', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
        Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    font-weight: 400;
    letter-spacing: -0.01em;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Main Container Layout */
.container {
    display: grid;
    grid-template-areas:
        "sidebar content";
    grid-template-columns: 280px 1fr;
    grid-template-rows: 1fr;
    height: 100vh;
    background: var(--bg-primary);
    box-shadow: 0 1px 3px var(--shadow-light);
    transition: background-color 0.3s ease;
}

.header {
    grid-area: header;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-primary);
    z-index: 100;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

.sidebar {
    grid-area: sidebar;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-secondary);
    overflow-y: auto;
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none; /* IE and Edge */
    height: calc(100vh - var(--header-height));
    scrollbar-width: none; /* Firefox */
    -ms-overflow-style: none; /* IE and Edge */
    transition: background-color 0.3s ease, border-color 0.3s ease;
    width: 280px;
    z-index: 999;
    top: var(--header-height);
    position: relative;
}

.sidebar::-webkit-scrollbar {
    display: none; /* Chrome, Safari, Opera */
}

.content {
    grid-area: content;
    padding: 2.5rem;
    padding-top: calc(2.5rem + var(--header-height));
    background: var(--bg-content);
    overflow-y: auto;
    font-size: 16px;
    line-height: 1.7;
    height: calc(100vh - var(--header-height));
    scrollbar-width: thin;
    scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
    transition: background-color 0.3s ease;
}

.content::-webkit-scrollbar {
    width: 8px;
}

.content::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}

.content::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 4px;
}

.content::-webkit-scrollbar-thumb:hover {
    background: var(--scrollbar-thumb-hover);
}

/* ===== CONTENT STYLING RULES ===== */

/* Headers */
.content h1,
.content .header-main {
    color: var(--text-primary);
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 3px solid var(--accent-primary);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    letter-spacing: -0.025em;
    transition: color 0.3s ease, border-color 0.3s ease;
}

.content h2,
.content .header-secondary {
    color: var(--text-secondary);
    font-size: 1.5rem;
    font-weight: 700;
    margin: 2.5rem 0 1rem 0;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-primary);
    position: relative;
    transition: color 0.3s ease, border-color 0.3s ease;
}

.content h2::after,
.content .header-secondary::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 60px;
    height: 2px;
    background: var(--accent-primary);
    transition: background-color 0.3s ease;
}

.content h3,
.content .header-tertiary {
    color: var(--text-secondary);
    font-size: 1.25rem;
    font-weight: 600;
    margin: 2rem 0 0.75rem 0;
    padding-bottom: 0.25rem;
    border-bottom: 1px solid var(--border-primary);
    transition: color 0.3s ease, border-color 0.3s ease;
}

.content h4,
.content .header-quaternary {
    color: var(--text-muted);
    font-size: 1.125rem;
    font-weight: 600;
    margin: 1.5rem 0 0.5rem 0;
    transition: color 0.3s ease;
}

/* Paragraphs */
.content p,
.content .paragraph {
    margin-bottom: 1.25rem;
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.7;
    transition: color 0.3s ease;
}

/* Lists */
.content ul,
.content ol,
.content .list {
    margin: 1.25rem 0;
    padding-left: 2rem;
}

.content li,
.content .list-item {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    line-height: 1.6;
    transition: color 0.3s ease;
}

.content li::marker,
.content .list-item::marker {
    color: var(--accent-primary);
    font-weight: 600;
    transition: color 0.3s ease;
}

/* Links */
.content a,
.content .link {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 500;
    border-bottom: 1px solid transparent;
    transition: all 0.2s ease;
    padding-bottom: 1px;
}

.content a:hover,
.content .link:hover {
    color: var(--accent-secondary);
    border-bottom-color: var(--accent-secondary);
    background: rgba(49, 130, 206, 0.05);
}

/* Strong text */
.content strong,
.content .strong,
.content .bold {
    color: var(--text-primary);
    font-weight: 700;
    background: linear-gradient(120deg, rgba(49, 130, 206, 0.1) 0%, rgba(49, 130, 206, 0.1) 100%);
    padding: 0.125rem 0.25rem;
    border-radius: 3px;
    transition: color 0.3s ease;
}

/* Italic text */
.content em,
.content .italic {
    color: var(--text-muted);
    font-style: italic;
    font-weight: 500;
    transition: color 0.3s ease;
}

/* Code blocks - See code-highlight.css for detailed styles */
/* Code highlighting and copy functionality are handled separately */

/* Terminal Window Styles */
.content .terminal,
.content .bash-window {
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 8px;
    margin: 1.5rem 0;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    transition: box-shadow 0.3s ease;
}

.content .terminal:hover,
.content .bash-window:hover {
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

/* Terminal Header */
.content .terminal-header,
.content .bash-header {
    background: linear-gradient(135deg, #2d2d2d 0%, #1a1a1a 100%);
    padding: 0.75rem 1rem;
    border-bottom: 1px solid #333;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.content .terminal-title,
.content .bash-title {
    color: #e0e0e0;
    font-size: 0.875rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.content .terminal-title::before,
.content .bash-title::before {
    content: '●';
    color: #ff5f56;
    font-size: 0.75rem;
}

.content .terminal-title::after,
.content .bash-title::after {
    content: '●';
    color: #ffbd2e;
    font-size: 0.75rem;
    margin-left: 0.25rem;
}

.content .terminal-controls,
.content .bash-controls {
    display: flex;
    gap: 0.25rem;
}

.content .terminal-control,
.content .bash-control {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #ff5f56;
    border: none;
    cursor: pointer;
    transition: opacity 0.2s ease;
}

.content .terminal-control:nth-child(2),
.content .bash-control:nth-child(2) {
    background: #ffbd2e;
}

.content .terminal-control:nth-child(3),
.content .bash-control:nth-child(3) {
    background: #27ca3f;
}

.content .terminal-control:hover,
.content .bash-control:hover {
    opacity: 0.8;
}

/* Terminal Content */
.content .terminal-content,
.content .bash-content {
    padding: 1rem;
    background: #1a1a1a;
    color: #e0e0e0;
    font-size: 0.875rem;
    line-height: 1.5;
    white-space: pre-wrap;
    overflow-x: auto;
}

.content .terminal-content code,
.content .bash-content code {
    background: transparent;
    color: inherit;
    padding: 0;
    border-radius: 0;
    font-family: inherit;
}

/* Command Line Styles */
.content .command-line,
.content .cmd-window {
    background: #0c0c0c;
    border: 1px solid #333;
    border-radius: 6px;
    margin: 1.5rem 0;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
    font-family: 'Consolas', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
    transition: box-shadow 0.3s ease;
}

.content .command-line:hover,
.content .cmd-window:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.5);
}

/* Command Line Header */
.content .command-header,
.content .cmd-header {
    background: #1a1a1a;
    padding: 0.5rem 1rem;
    border-bottom: 1px solid #333;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.content .command-prompt,
.content .cmd-prompt {
    color: #00ff00;
    font-weight: bold;
    font-size: 0.875rem;
}

.content .command-path,
.content .cmd-path {
    color: #87ceeb;
    font-size: 0.875rem;
}

/* Command Line Content */
.content .command-content,
.content .cmd-content {
    padding: 1rem;
    background: #0c0c0c;
    color: #ffffff;
    font-size: 0.875rem;
    line-height: 1.6;
    white-space: pre-wrap;
    overflow-x: auto;
}

.content .command-content code,
.content .cmd-content code {
    background: transparent;
    color: inherit;
    padding: 0;
    border-radius: 0;
    font-family: inherit;
}

/* Command Input Line */
.content .command-input,
.content .cmd-input {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.content .command-prompt-symbol,
.content .cmd-prompt-symbol {
    color: #00ff00;
    font-weight: bold;
}

.content .command-text,
.content .cmd-text {
    color: #ffffff;
    flex: 1;
}

/* Command Output */
.content .command-output,
.content .cmd-output {
    color: #cccccc;
    margin-top: 0.5rem;
    padding-left: 1rem;
    border-left: 2px solid #333;
}

/* Dark mode adjustments for terminal styles */
[data-theme="dark"] .content .terminal,
[data-theme="dark"] .content .bash-window {
    background: #0a0a0a;
    border-color: #444;
}

[data-theme="dark"] .content .terminal-header,
[data-theme="dark"] .content .bash-header {
    background: linear-gradient(135deg, #1a1a1a 0%, #0a0a0a 100%);
    border-bottom-color: #444;
}

[data-theme="dark"] .content .terminal-content,
[data-theme="dark"] .content .bash-content {
    background: #0a0a0a;
}

[data-theme="dark"] .content .command-line,
[data-theme="dark"] .content .cmd-window {
    background: #000000;
    border-color: #444;
}

[data-theme="dark"] .content .command-header,
[data-theme="dark"] .content .cmd-header {
    background: #1a1a1a;
    border-bottom-color: #444;
}

[data-theme="dark"] .content .command-content,
[data-theme="dark"] .content .cmd-content {
    background: #000000;
}

/* Blockquotes */
.content blockquote,
.content .quote,
.content .blockquote {
    background: var(--blockquote-bg);
    border-left: 4px solid var(--accent-primary);
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 6px 6px 0;
    font-style: italic;
    color: var(--text-muted);
    position: relative;
    transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
}

.content blockquote::before,
.content .quote::before,
.content .blockquote::before {
    content: '"';
    position: absolute;
    top: -0.5rem;
    left: 1rem;
    font-size: 3rem;
    color: var(--accent-primary);
    font-family: serif;
    line-height: 1;
    transition: color 0.3s ease;
}

.content blockquote p,
.content .quote p,
.content .blockquote p {
    margin: 0;
}

/* Tables */
.content table,
.content .table {
    width: auto;
    min-width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
    border: 1px solid var(--border-primary);
    transition: border-color 0.3s ease;
}

.content th,
.content .table-header {
    background: var(--table-stripe);
    border: 1px solid var(--border-primary);
    padding: 0.5rem 0.75rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-secondary);
    white-space: nowrap;
    transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
}

/* First header cell - top left corner */
.content th:first-child,
.content .table-header:first-child {
    border-top-left-radius: 6px;
}

/* Last header cell - top right corner */
.content th:last-child,
.content .table-header:last-child {
    border-top-right-radius: 6px;
}

.content td,
.content .table-cell {
    border: 1px solid var(--border-primary);
    padding: 0.5rem 0.75rem;
    color: var(--text-muted);
    transition: border-color 0.3s ease, color 0.3s ease;
}

/* Last row first cell - bottom left corner */
.content tr:last-child td:first-child,
.content .table-row:last-child .table-cell:first-child {
    border-bottom-left-radius: 6px;
}

/* Last row last cell - bottom right corner */
.content tr:last-child td:last-child,
.content .table-row:last-child .table-cell:last-child {
    border-bottom-right-radius: 6px;
}

.content tr:nth-child(even),
.content .table-row:nth-child(even) {
    background: var(--table-stripe);
    transition: background-color 0.3s ease;
}

/* Horizontal rules */
.content hr,
.content .divider {
    border: none;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent-primary), transparent);
    margin: 2rem 0;
    transition: background 0.3s ease;
}

/* Definition lists */
.content dl,
.content .definition-list {
    margin: 1.5rem 0;
}

.content dt,
.content .definition-term {
    font-weight: 700;
    color: var(--text-primary);
    margin-top: 1rem;
    transition: color 0.3s ease;
}

.content dd,
.content .definition-description {
    margin-left: 1rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

/* Special content classes */
.content .note {
    background: rgba(49, 130, 206, 0.1);
    border-left: 4px solid var(--accent-primary);
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 6px 6px 0;
    color: var(--accent-secondary);
    transition: border-color 0.3s ease, color 0.3s ease, background-color 0.3s ease;
}

.content .note p:last-child {
    margin-bottom: 0;
}

.content .warning {
    background: rgba(237, 137, 54, 0.1);
    border-left: 4px solid #ed8936;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 6px 6px 0;
    color: #c05621;
    transition: background-color 0.3s ease;
}

.content .warning p:last-child {
    margin-bottom: 0;
}

.content .error {
    background: rgba(245, 101, 101, 0.1);
    border-left: 4px solid #f56565;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 6px 6px 0;
    color: #c53030;
    transition: background-color 0.3s ease;
}

.content .error p:last-child {
    margin-bottom: 0;
}

.content .success {
    background: rgba(72, 187, 120, 0.1);
    border-left: 4px solid #48bb78;
    padding: 1rem 1.5rem;
    margin: 1.5rem 0;
    border-radius: 0 6px 6px 0;
    color: #2f855a;
    transition: background-color 0.3s ease;
}

.content .success p:last-child {
    margin-bottom: 0;
}

/* Time Complexity Display Styles */
.content .complexity-comparison {
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
    border: 2px solid var(--border-primary);
    border-radius: 12px;
    margin: 2rem 0;
    overflow: hidden;
    box-shadow: 0 4px 20px var(--shadow-light);
}

.content .complexity-header {
    background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
    color: white;
    padding: 1.5rem;
    text-align: center;
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: -0.02em;
}

.content .complexity-content {
    padding: 2rem;
}

.content .complexity-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.content .complexity-row:last-child {
    margin-bottom: 0;
}

.content .complexity-item {
    background: var(--bg-primary);
    border: 1px solid var(--border-primary);
    border-radius: 8px;
    padding: 1.5rem;
}

.content .complexity-title {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.content .complexity-title::before {
    content: '';
    width: 4px;
    height: 20px;
    background: var(--accent-primary);
    border-radius: 2px;
}

.content .complexity-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: var(--accent-primary);
    color: white;
    border-radius: 20px;
    font-weight: 700;
    font-size: 0.875rem;
    margin-bottom: 1rem;
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
}

.content .complexity-description {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.content .complexity-details {
    background: var(--bg-secondary);
    border-radius: 6px;
    padding: 1rem;
    margin-top: 1rem;
}

.content .complexity-detail-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-primary);
}

.content .complexity-detail-item:last-child {
    border-bottom: none;
}

.content .complexity-detail-label {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.content .complexity-detail-value {
    font-weight: 700;
    color: var(--accent-primary);
    font-family: 'SF Mono', 'Monaco', 'Inconsolata', 'Roboto Mono', monospace;
}

.content .complexity-note {
    background: rgba(49, 130, 206, 0.1);
    border-left: 4px solid var(--accent-primary);
    padding: 1rem;
    margin-top: 1rem;
    border-radius: 0 6px 6px 0;
    font-size: 0.875rem;
    color: var(--accent-secondary);
}

/* Dark mode adjustments for complexity styles */
[data-theme="dark"] .content .complexity-comparison {
    background: linear-gradient(135deg, #2d3748 0%, #1a202c 100%);
    border-color: #4a5568;
}

[data-theme="dark"] .content .complexity-item {
    background: #2d3748;
    border-color: #4a5568;
}

[data-theme="dark"] .content .complexity-details {
    background: #1a202c;
}

[data-theme="dark"] .content .complexity-detail-item {
    border-bottom-color: #4a5568;
}

[data-theme="dark"] .content .complexity-note {
    background: rgba(99, 179, 237, 0.1);
    color: #90cdf4;
}

/* Responsive design for complexity comparison */
@media (max-width: 768px) {
    .content .complexity-row {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .content .complexity-content {
        padding: 1.5rem;
    }
    
    .content .complexity-header {
        padding: 1rem;
        font-size: 1.125rem;
    }
    
    .content .complexity-item {
        padding: 1rem;
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .container {
        grid-template-columns: 250px 1fr;
    }
    
    .sidebar {
        width: 250px;
    }
    
    .content {
    }
}

@media (max-width: 768px) {
    .container {
        grid-template-areas:
            "content";
        grid-template-columns: 1fr;
        grid-template-rows: 1fr;
    }

    .sidebar {
        position: fixed;
        top: 0;
        left: -280px;
        width: 280px;
        height: 100vh;
        z-index: 1001;
        transform: translateX(0);
        transition: transform 0.3s ease;
        border-right: none;
        border-bottom: none;
        max-height: none;
    }
    
    .sidebar.mobile-open {
        transform: translateX(280px);
    }

    .content {
        padding: 1.5rem;
        padding-top: calc(1.5rem + var(--header-height));
        font-size: 15px;
        height: calc(100vh - var(--header-height));
        margin-left: 0;
    }

    .content h1,
    .content .header-main {
        font-size: 1.875rem;
    }

    .content h2,
    .content .header-secondary {
        font-size: 1.375rem;
    }

    .content pre,
    .content .code-block {
        padding: 1rem;
        font-size: 0.8rem;
    }
    
    /* Terminal and Command Line responsive styles */
    .content .terminal,
    .content .bash-window,
    .content .command-line,
    .content .cmd-window {
        margin: 1rem 0;
        border-radius: 6px;
    }
    
    .content .terminal-header,
    .content .bash-header,
    .content .command-header,
    .content .cmd-header {
        padding: 0.5rem 0.75rem;
    }
    
    .content .terminal-title,
    .content .bash-title {
        font-size: 0.8rem;
    }
    
    .content .terminal-content,
    .content .bash-content,
    .content .command-content,
    .content .cmd-content {
        padding: 0.75rem;
        font-size: 0.8rem;
        line-height: 1.4;
    }
    
    .content .command-prompt,
    .content .cmd-prompt,
    .content .command-path,
    .content .cmd-path {
        font-size: 0.8rem;
    }
}